This invention relates to a refrigerating apparatus, more particularly to an improvement in a refrigerating apparatus in which at least two evaporators are controlled to different temperatures.
Generally, a refrigerator having a freezing compartment and refrigerating compartment, which are controlled to different temperatures, has separate evaporators for the freezing compartment and for the refrigerating compartment because separate cooling is necessary for each compartment. Although the separate evaporators are provided, it is preferable that a compressor and a condenser are used in common to those separate evaporators. Accordingly, refrigerant feed control to one or both of the evaporators is necessary. For example, the refrigerant is always fed to the freezing evaporator while the refrigerant is selectively fed to the refrigerating evaporator by the function of a solenoid valve when the compressor is energized. Thus, separate temperature control is attained by a control of the solenoid valve in conjunction with a control to the compressor.
However, such a solenoid valve has a mechanically movable valve which is buried in a heat-insulating material so that it is difficult to maintain or inspect the valve after the refrigerator is assembled. Accordingly, the life and the reliability of the refrigerator are not sufficient, and, moreover, this structure is too expensive.
Feed control devices or arrangements which employ a vapor bubble pump providing valve action to the refrigerant have been developed. Thus, mechanical movable parts can be eliminated from the feed control devices of the refrigerator. Such arrangements are disclosed, for example, in the U.S. Pat. No. 2,697,331.
However, the operation of the vapor bubble pumps tends to suffer from the ambient temperature of the vapor bubble pumps. Further, several parts forming the feed control arrangement are required to be disposed in a predetermined position when such parts are installed in the refrigerator.